rsync_backup: Initial version of role

roles/rsync_backup/files/backup-daily.sh

@@ -0,0 +1,150 @@
+#!/bin/sh
+
+set -eu
+
+umask 077
+
+ROTATED=30
+
+CONFDIR="/etc/rsync-backup"
+DESTDIR="/srv/backup"
+LOGDIR="/var/log/rsync-backup"
+RUNDIR="/var/run/rsync-backup"
+
+find_rotated() {
+    # sort dailys from oldest to newest, daily.7 daily.6 daily.5 ...
+    find "$1" -mindepth 1 -maxdepth 1 -type d -name "daily.*" | sort -V -r
+}
+
+rotate_dirs() {
+    for host in "$@"; do
+        # rotate dailys starting from oldest
+        if [ ! -d "${DESTDIR}/${host}" ]; then
+            continue
+        fi
+        find_rotated "${DESTDIR}/${host}" | while read -r dir; do
+            ext="${dir##*.}"
+            next="${dir%.*}.$((ext+1))"
+            mv "$dir" "$next"
+        done
+    done
+    # compress logs over 1 day old
+    find "$LOGDIR" -type f -name '*.log' -mtime +1 -execdir gzip -f {} ';'
+}
+
+prune_dirs() {
+    for host in "$@"; do
+        # remove oldest dailys
+        find_rotated "${DESTDIR}/${host}" | while read -r dir ; do
+            num="$(basename "$dir" | sed -e 's/^daily.//')"
+            if [ "$num" -gt $ROTATED ]; then
+                rm -rf "$dir"
+            fi
+        done
+    done
+    # remove logs over ROTATED*2 days old
+    find "$LOGDIR" -type f -name '*.log.gz' -mtime +$((ROTATED*2)) -delete
+}
+
+rsync_pull() {
+    dirs=""
+    opts=""
+    host="$1"
+    conf="${CONFDIR}/${host}.conf"
+    if [ -s "$conf" ] && [ -x "$conf" ]; then
+        # shellcheck source=/dev/null
+        . "$conf" || return
+    else
+        echo "skipped: ${1}" 1>&2
+        return
+    fi
+
+    lockdir="${RUNDIR}/${host}.lock"
+    mkdir -m 0755 "$lockdir" || return
+
+    if [ "$host" = "$(hostname)" ]; then
+        # skip ssh for localhost
+        set -- $dirs
+    else
+        set -- $(for d in $dirs; do echo "${host}:${d}" ; done)
+    fi
+
+    base="${DESTDIR}/${host}"
+    if [ ! -d "$base" ]; then
+        mkdir -m 0700 "$base" || return
+    fi
+    dest="${base}/daily.0"
+    last="${base}/daily.1"
+    if [ ! -d "$dest" ]; then
+        mkdir -m 0700 "$dest" || return
+    fi
+    if [ -d "$last" ]; then
+        # hardlink unchanged files to previous daily
+	opts="--ignore-existing --link-dest=${last}"
+    fi
+
+    logfile="${LOGDIR}/${host}.$(date +%Y%m%d-%H%M%S).log"
+    if ! /usr/local/bin/rsync \
+        -e "ssh -o BatchMode=yes -i ${CONFDIR}/id_ed25519" \
+	-Raqxz --no-devices $opts \
+        --log-file="$logfile" \
+	"$@" "$dest"
+    then
+        echo "rsync log: ${logfile}" 1>&2
+    fi
+    rmdir "$lockdir"
+}
+
+if [ ! -d "$DESTDIR" ]; then
+    echo "ERROR: ${DESTDIR} does not exist" 1>&2
+    exit 1
+fi
+
+if [ ! -d "$LOGDIR" ]; then
+    echo "ERROR: ${LOGDIR} does not exist" 1>&2
+    exit 1
+fi
+
+if [ ! -d "$RUNDIR" ]; then
+    mkdir -m 0755 "$RUNDIR"
+fi
+
+ALL=false
+PRUNE=false
+ROTATE=false
+while getopts "apr" OPT; do
+    case "$OPT" in
+        a)
+            ALL=true
+            ;;
+        p)
+            PRUNE=true
+            ;;
+        r)
+            ROTATE=true
+            ;;
+        *)
+            echo "Usage: $(basename "$0") [-apr] [host ...]" 1>&2
+            exit 1
+            ;;
+    esac
+done
+shift $((OPTIND-1))
+
+mkdir -m 0755 "${RUNDIR}/daily.lock"
+trap 'rmdir "${RUNDIR}/daily.lock"' EXIT
+
+if [ $ALL ]; then
+    for conf in "${CONFDIR}"/*.conf ; do
+        host="$(basename "$conf" ".conf")"
+        set -- "$host" "$@"
+    done
+fi
+
+$ROTATE && rotate_dirs "$@"
+
+for host in "$@" ; do
+    rsync_pull "$host"
+done
+
+$PRUNE && prune_dirs "$@"